Process for treating nylon textile materials



2,997,773 PROCESS FOR TREATING NYLON TEXTILE MATERIALS Philip B. Roth, Somerville, and Donald T. Wallworlr, Bound Brook, N.J., assignors to American Cyanamid Company, New York, N.Y., a corporation of Maine N Drawing. Filed Nov. 15, 1957, Ser. No. 696,617 6 Claims. (Cl. 2876) This invention relates to a method for removing cellu lose acetate draw threads from resin-treated synthetic nylon web lace material.

In a process for the manufacture of nylon net fabric, such as nylon lace of the type suitable for use as ruflles, trim and the like; two or more strips or bands of the nylon net are woven or knitted simultaneously with the nylon bands separated by narrow strips or sections composed of cellulose acetate fibers called draw threads. By employing this technique, it is possible to weave or knit several bands of the nylon net as a single piece of goods of standard width on a conventional weaving or knitting machine. As a result of this technique, subsequent handling operations of the web of lace material may also be carried out on standard textile machines. The separation of the individual bands of nylon net is normally accomplished by dissolving the cellulose acetate draw threads in a suitable solvent, usually acetone. By this process, the bands or strips of nylon are obtained with smooth edges, which may be straight or scalloped as desired.

Nylon fabric, in its natural form, is a soft and limp material. For many of the useful applications of nylon net, it is desirable or essential that the nylon be firm or stiff. In order to modify the hand and also prevent shrinking and puckering, the fabrics are treated with thermosetting resinous materials and in particular thermosetting aminoplast resinous materials, such as melamineformaldehyde resins, urea-formaldehyde resins, and the like.

While the application of such thermosetting aminoplast resins to a web of nylon lace material results in imparting stiffness to the nylon material, the presence of the thermosetting resin functions to prevent the complete removal of the cellulose acetate fiber draw threads through their dissolution in suitable solvent. This results in portions of the draw threads remaining attached to the individual bands of nylon, giving the edges a ragged and unattractive appearance. The result is that some time before the nylon lace appears in its final form that the ragged edges must be clipped or otherwise mechanically removed, which requires additional time and man hours.

A further difficulty which presents itself in attempting to remove the cellulose acetate draw threads from resintreated web lace material, in accordance with presently commercially adapted procedures, is that in attempting to dissolve the acetate draw threads in a suitable solvent such as acetone, fragments from the draw thread section may be removed, but are not fully dissolved. These undissolved fragments frequently settle on the nylon band portions in the dissolving bath, and are difficult to remove.

It is apparent that the resinous finishes could be applied to the individual strips of nylon lace after the removal of the acetate draw threads, but this would be difficult and expensive, requiring special machines and techniques, and would result in the loss of the advantage ZQWJ'ZB Patented Aug. 29, 1961 of being able to treat several strips or bands of nylon net simultaneously, in a single piece of goods and on standard textile machinery.

Therefore, it is an object of the present invention to provide a method whereby cellulose acetate draw threads may be readily and cleanly removed from a web of nylon lace material that has been treated with a thermosetting aminoplast resin of the type employed to impart a durabie stiff finish to said nylon.

It is a further object to provide such a process whereby a durable stiff finish may be imparted to nylon lace material, which finish permits substantially complete dissolution of cellulose acetate draw threads in a suitable solvent.

These and other objects and advantages of the present invention will become more apparent from the detailed description of this invention as it is set forth hereinbelow.

According to the present invention, a process is provided for removing cellulose acetate draw threads by dissolution in a solvent therefor from a thermosetting aminoplast resin-treated nylon web lace material. This process comprises applying to said web lace material containing cellulose acetate draw threads a composition comprising a thermosetting aminoplast resin and at least 0.001%, based on the weight of the web lace material, of a surface active agent capable of retaining its ability to permit wetting of the draw threads by a solvent, after drying and curing the aminoplast resin. The web lace material is then dried and the resin cured thereon to impart the desirable stiff finish, and the cellulose acetate draw threads are dissolved in a suitable solvent, which is inert with respect to the nylon portion of the material and the cured resin finish.

The thermosetting aminoplast resins contemplated for use in the present process may be any of the aminoplast resins used to impart a stiff finish to nylon. Thus, for example, melamine-formaldehyde resins which may contain up to 6 moles of combined formaldehyde and up to 6 moles of combined alcohol per mole of melamine may be employed. Specific examples of resins in this class are trimethyl trirnethylol melamine, tetramethyl pentarnethylol melamine, and the like.

In addition, the guanamines and substituted guanamines and their formaldehyde condensates, including their alkylated derivatives, are contemplated. Specific examples of such compounds include the formaldehyde and alkylated formaldehyde derivatives of acetoguanamine, cyanopropioguanamine, lactoguanamine, methoxyacetoguanamine, ethoxyacetoguanamine, methoxymethoxyacetoguanamine, and the like.

The urea and thiourea-formaldehyde condensates and their alkylated derivatives may also be employed on nylon to achieve a modification of the hand and shrinkage control. In addition, the cyclic ureas, their formaldehyde condensates and alkylated derivatives may be employed. Thus, for example, these reaction products of ethylene urea, ethylene thiourea, 1,2-propylene urea, 1,3-propylene urea, and the like, may :be employed.

The formaldehyde condensates and alkylated derivatives of thiobis amides, as for example, thiobis-for 1.- amide, thiobis-acetamide, thiobis-propionamide, and the like, may be employed.

Resins from these known classes of aminoplasts may be employed singly or in combination with one another. With respect to the cyclic ureas, it is frequently desirable to employ a melamine or urea-formaldehyde resin in conjunction therewith to impart the necessary stiffness.

Regardless of the aminoplast material employed, it is preferably water soluble, and in monomeric form. However, the nonhydrophobing lower order polymers are contemplated. In all cases, the alcohol employed for alkylation is preferably an aliphatic monohydric alcohol having from 1 to 4 carbon atoms, i.e. methyl, ethyl, propyl and butyl alcohol, employed either alone or in combination with one another. Preferably, the alkylating alcohol is methyl alcohol. 7

The preferred class of thermosetting aminoplast resins are the melamine-formaldehyde resins, including their alkylated condensates, as they are identified hereinabove.

In order to impart a durable stiff finish to nylon lace material, normally from between about 2 and about of the thermosetting aminoplast resin is applied, based on the weight of the nylon material. An appreciable effect, however, may be obtained with as little as 0.1% of resin. With respect to the upper limit, for the most part, it is a matter of choice which is dictated by the desired degree of stiffness sought. Thus, for example, amounts substantially in excess of 10% may be employed where extremely stiif hands are sought, as for example, amounts up to 50 and 60% of the resin solids, based on the weight of the fabric may be applied.

The surface active agent must be one which is durable and retains its ability to permit wetting of the acetate draw threads by a suitable solvent, after drying and curing of the resin finish in intimate association therewith on the web lace material. It should be noted that the inclusion of a surface active agent in a suitable solvent bath, instead of intimately associating it on the fabric with cured resin, will not result in substantially complete removal of the acetate draw threads. The surface active agent is preferably applied from the same or is in the same treating solution as is the thermosetting aminoplast resin, and the minimum elfective amount of a surface active agent appears to be approximately 0.001%, based on the weight of the fabric. Preferably, the amount of surface active agent employed should be between approximately 0.01 and about 1%, based on the weight of the fabric. Amounts in excess of 1.0% appear to do no harm; however, economics dictate that amounts in excess of about 1.0% do not substantially improve the effectiveness of the process.

Of all the suitable surface active agents, the non-ionic surface active agents as a class are greatly preferred. To a lesser extent, cationic and anionic surface active agents, as well as mixtures of the latter two, have been employed with success.

Among the non-ionic surface active agents, the preferred group, found to be particularly suited for use in the present invention, are the alkylaryl polyether alcohols, such as the reaction product of 1 mole of nonyl phenol and about 9 /2 moles of ethylene oxide. In addition, the polyethylene glycol esters of oleic acid (Nonisol 200) the polyethylene glycol tert.-dodecyl thioether (Nonic 234) and diglycol stearate are suited for use in the present invention.

As examples of suitable cationic surface active agents which are effective in the present process, ethanolated alkyl guanidine-amine complexes of the type disclosed in Us. Patent No. 2,574,510, substituted oxazolines (Alkaterge C) and fatty carbamides, the latter being prepared in accordance with US. Patents 2,304,113 and 2,304,369, are illustrative.

With respect to anionic surface active agents, fatty carbamide salts (Ahcovel R) are suited, and mixed cationic and anionic long-chain derivatives, such as a mixture of octadecylamine and octadecyl guanidine salts of octadecyl carbamic acid and ethylene oxide plus N- octadecyl disodium sulfosuccinate, are suited for use in the present invention.

The thermosetting aminoplast resin and surface active agent composition may be applied by any of the conventional textile finishing techniques.

Thus for example, it

may be applied by immersion, submersion, spraying, padding, or any of the other well-known finishing techniques. Because of the large number of mills which employ padding procedures, padding is the preferred method of applying the thermosetting aminoplast resin-surface active agent composition.

The thermosetting aminoplast resin is preferably cured on the web of nylon lace material by the action of heat alone. Although the process of the present invention has been effective to some extent, when conventional aminoplast accelerators, as for example, diammonium hydrogen phosphate, magnesium chloride, ammonium sulfate, and the like, are employed as curing accelerators, the results are noticeably and distinctly less satisfactory. According to the preferred procedure, when curing accelerators are not employed and the thermosetting aminoplast resin is cured by the action of heat alone, temperatures between the range of about 200 to 600 F. at times of from between 8 minutes and 5 seconds, respectively, may normally be employed. Preferably, heat curing is effected at a temperature of from between 275 and 400 F. for from 6 minutes to 15 seconds, respectively. Prior to curing of the resin, the fabric may be dried or the drying and curing step may be carried out simultaneously. If carried out separately, the fabric is preferably dried at a temperature of about 225 F. followed by curing within the temperature range indicated above, or if dried and cured simultaneously, the times and temperatures may range from between 200 and 600 F. for from 8 minutes to about 5 seconds, respectively.

The solvent for the acetate draw threads employable in the present process may be any material which is solvent for or will dissolve the said draw threads and which is inert to the nylon bands of the web lace material. The preferred solvent for use in the present invention is acetone. However, other solvents may be employed, such as ethyl acetate, glacial acetic acid, and the like.

In order to illustrate the present invention, the following example and tabulated information are provided primarily by way of illustration. No details found therein should be construed as limitations on the present invention, except as they appear in the claims. All parts and percentages are by weight unless otherwise indicated.

EXAMPLE 1 A plurality of samples of webs of nylon lace material having cellulose acetate draw threads were treated with an exemplary thermosetting aminoplast resin, namely trimethyl trimethylol melamine. To a plurality of pad bath solutions of trimethyl trimethylol melamine resin, there was added various amounts of the various surface active agents recorded in the table hereinbelow. Thereafter, a plurality of the web of nylon lace material having a cellulose acetate draw thread was impregnated through with the pad bath solutions and the excess solution was squeezed out by passing the fabric between rolls, using 4.7 tons of pressure, so that approximately 70% of the solution was left on the fabric. The padding solutions contained 8% of the melamine resin. Two dips and two nips were used in each instance. The fabric, after drying and curing at 300 F., contained approximately 5.6% of resin solids, based on the weight of the web of lace material.

The efiectiveness of the treatment with the thermosetting resin and the various surface active agents was then tested by immersing the web of nylon lace material in acetone for 1 hour at 20 C. At the end of this period, the condition of the cellulose acetate draw threads was observed. If no residue of draw threads was visible, the application was considered to be completely satisfactory.

In the less satisfactory applications, there were increasing amounts of draw threads remaining attached to the nylon lace. Table I shows the results of the experiments and tests.

Table I Surface Active Agent Residue of Cel- Percent Percent; lulose Acetate Name or Type Class In Solu- OWF tion Control (no surface- Considerable.

active agent). Allllryilarylpolyether alco- Non-ionic. 0.025 0.018 Very slight.

l do.- 0.05 0.035 Do. "do. 0.10 0.07 Do. do 0.15 0.11 Do. do. 0.2 0. 14 None. do 0.3 0. 21 Do. do 0.5 0.35 Do. Do do 1.0 0. 70 Do. Polyethylene glycolester do 0.5 0.35 Very slight.

of oleic acid. Polyethylene glycol tert.- d 0. 42 0. 29 Do.

dodecyl thioether. Diglycol stearate d0 0. 0.35 Do. Ethanolatedalkyl guani- Cati0nic 0.2 0. 14 None.

dine amine complex. Substituted oxazoline 0. 5 0.35 Very slight. Fatty carbamides. 0. 23 O. 16 Slight. Fatty carbamide salts. 0.25 0. 18 Do. Octadecylamine and 00- Mixed. 0. 07 0.05 None.

tadecylguanidine salts of octadecyl carbamic acid and 6 moles of ethylene oxide plus N- octadecyl disodium sulfosuocinate.

The results in Table I clearly indicate that in accordance 'with the present process a substantially complete removal of the cellulose acetate draw threads may be readily and conveniently accomplished. It further indicates that while certain species of surface active agents appear to be more effective than others, even at somewhat lower concentrations on the weight of the fabric, that substantially complete removal of the draw thread may be readily accomplished. This is particularly true with respect to the nonionic surface active agents.

We claim:

1. A process for removing cellulose acetate draw threads from a web of nylon lace material having a durable thermosetting aminoplast resin finish thereon, which comprises applying to said web of nylon lace material a thermosetting aminoplast resin and at least 0.001% based on the weight of the web lace material, of a surface active agent capable of retaining its ability to permit wetting of the draw threads by a solvent for acetate after drying and curing of the aminoplast resin, drying said web lace fabric and curing said aminoplast resin thereon, and dissolving said acetate draw threads in said solvent, said solvent being inert with respect to the nylon and the cured aminoplast resin finishes.

2. A process according to claim 1 in which the solvent for the acetate is acetone.

3. A process according to claim 1 in which the surface active agent is a non-ionic surface active agent and in which it is applied in an amount of from between 0.01 and 1%, based on the weight of the web lace material.

4. A process according to claim 1 in which the thermosetting aminoplast resin is a melamine-formaldehyde resin.

5. A process according to claim 1 in which the aminoplast resin is a melamine-formaldehyde resin and is applied in amounts of from between 0.1 and by weight, based on the Weight of the web lace material.

6. A process according to claim 1, in which the aminoplast resin and surface active wetting agent are applied simultaneously to a web of nylon lace material.

References Cited in the file of this patent UNITED STATES PATENTS 1,665,230 Spalding Apr. 10, 1928 2,297,135 Davis et al. Sept. 29, 1942 2,332,738 Meade Oct. 26, 1943 2,437,735 Getaz Mar. 16, 1948 2,601,770 Goldsmith July 1, 1952 2,795,513 Rossin June 11, 1957 2,804,441 Nickerson Aug. 27, 1957 FOREIGN PATENTS 566,507 Great Britain Jan. 2, 1945 OTHER REFERENCES Textile Chemicals and Auxiliaries, by Henry C. Speel, Reinhold Publishing Corp, 1952, Library of Congress 5241861. (Copy available in Division 50, pages 272, 367 and 368 relied on.) 

1. A PROCESS FOR REMOVING CELLULOSE ACETATE DRAW THREADS FROM A WEB OF NYLON LACE MATERIAL HAVING A DURABLE THERMOSETTING AMINOPLAST RESIN FINISH THEREON, WHICH COMPRISES APPLYING TO SAID WEB OF NYLON LACE MATERIAL A THERMOSETTING AMINOPLAST RESIN AND AT LEAST 0.001%, BASED ON THE WEIGHT OF THE WEB LACE MATERIAL, OF A SURFACE ACTIVE AGENT CAPABLE OF RETAINING ITS ABILITY TO PERMIT WETTING OF THE DRAW THREADS BY A SOLVENT FOR ACETATE AFTER DRYING AND CURING OF THE AMINOPLAST RESIN, DRYING SAID WEB LACE FABRIC AND CURING SAID AMINOPLAST RESIN THEREON, AND DISSOLVING SAID ACETATE DRAW THREADS IN SAID SOLVENT, SAID SOLVENT BEING INERT WITH RESPECT TO THE NYLON AND THE CURED AMINOPLAST RESIN FINISHES. 